This invention relates to a method of producing carbide products, such as silicon carbide.
Silicon carbide powder as well as other carbide powders are useful in the fabrication of highly stressed ceramic parts, such as those employed in heat engines, turbo-charger rotors and heat exchangers. Such parts are fabricated by consolidating the carbide powder into the desired shape, followed by sintering the consolidated part at temperatures of about 2,000.degree. C. In order to fabricate parts having acceptable mechanical strength, it is generally desirable to use a finely divided powder made up of highly uniform, submicron particles.
Heretofore, the primary method of making silicon carbide involves electrically heating a mixture of solid carbon and silica (silicon dioxide, i.e. sand). Large chunks are produced by this technique which must be subjected to mechanical grinding to reduce the particles to the necessary submicron diameters. Such grinding adds undesirable metal impurities to the product, requires excessive energy and is also time consuming.